(1) Field of the Invention
This invention relates to chemical treating apparatus for performing a required treatment of substrates such as semiconductor wafers, glass substrates for photo masks, glass substrates for liquid crystal displays or substrates for optical disks, by supplying surfaces of the substrates with a treating solution such as a resist solution, developer or rinse solution. More particularly, the invention relates to a technique for controlling the temperature of a treating solution efficiently without enlarging an apparatus.
(2) Description of the Related Art
A known example of the chemical treating apparatus noted above is a spin coating apparatus which delivers a treating solution to the surface of a substrate to form a film thereon. The known spin coating apparatus will be described with reference to FIGS. 1 and 2. FIG. 1 is a sectional view of a treating solution supply arm 110 of the known spin coating apparatus. FIG. 2 is a side view of the known spin coating apparatus. As shown in FIGS. 1 and 2, this spin coating apparatus includes a turntable 100 for supporting and spinning a wafer W in horizontal posture, and the treating solution supply arm 110 for delivering a treating solution to the wafer W.
The treating solution supply arm 110 is connected at a proximal end thereof to a support block 111, and has a nozzle 112 attached to a distal end to be movable in X, Y and Z directions. The treating solution supply arm 110 has an arm portion 113 of triple pipe construction including a treating solution pipe 114, a temperature control pipe 115 and a metal pipe 116. The nozzle 112 is connected to the distal end of the treating solution supply arm 110 for delivering the treating solution to the wafer W. The treating solution pipe 114 is connected at a forward end thereof to the nozzle 112, and at the other end to a treating solution source (not shown).
Where the treating solution is a resist solution, for example, it is known that, depending on the temperature of the resist solution, the resist film formed on the wafer W is variable in thickness in the direction of the plane of wafer W. Thus, the spin coating apparatus has the temperature control pipe 115 surrounding the treating solution pipe 114 to adjust the temperature of the treating solution in the treating solution pipe 114.
Specifically, with the temperature control pipe 115 interposed between the treating solution pipe 114 and metal pipe 116, a forward passage 117 for temperature control water is formed between the treating solution pipe 114 and temperature control pipe 115, and a return passage 118 for the temperature control water between the temperature control pipe 115 and metal pipe 116. The temperature control water (i.e. water adjusted to a constant temperature) supplied from an external thermostatic tank is caused to flow through the forward passage 117 along the treating solution pipe 114 toward the nozzle 112, thereby to adjust the treating solution in the treating solution pipe 114 to a predetermined temperature. The temperature control water having reached the nozzle 112 is directed into the return passage 118 to flow back to the thermostatic tank. With this construction, the treating solution delivered from the nozzle 112 is adjusted to the predetermined temperature to form a film in uniform thickness over the surface of wafer W.
The conventional construction noted above has the following drawbacks.
Where, as shown in FIGS. 1 and 2, the temperature control water is circulated along the temperature control pipe 115 surrounding the treating solution pipe 114 having the nozzle 112 attached to the forward end, the large diameter of the temperature control pipe 115 allows only a limited curvature for the treating solution pipe 114 in time of movement of the nozzle 112. Consequently, a large vertical space is required above the wafer W, which rules out the possibility of making the apparatus vertically compact.
With an increasingly refined structure of semiconductor devices and larger diameter of substrates of recent years, new types of treating solutions have been developed and substrates are now supplied with a greater variety of treating solutions. Thus, it is necessary to provide a temperature control pipe 115 for every type of treating solution. Piping paths become complicated. The number of circulators must also be increased to adjust the temperature of the temperature control water in each temperature control pipe 115. All this requires an enlarged and complicated apparatus.
This invention has been made having regard to the state of the art noted above, and its object is to provide a chemical treating apparatus having a compact construction and yet is capable of controlling the temperature of a treating solution efficiently.
The above object is fulfilled, according to this invention, by a chemical treating apparatus for performing a predetermined treatment of a principal surface of a substrate by delivering a treating solution thereto, the apparatus comprising a treating solution delivery nozzle for delivering the treating solution to the principal surface of the substrate, the nozzle including a treating solution reservoir adjacent a tip end thereof for storing the treating solution, and a temperature control device for holding the treating solution reservoir to control temperature of the treating solution in the treating solution reservoir through heat exchange with the treating solution.
According to this invention, the treating solution reservoir adjacent the tip of the nozzle is held to control the temperature of the treating solution in the reservoir by heat exchange. The temperature-controlled treating solution in the reservoir is delivered to the substrate for treatment. It is therefore possible to dispense with the temperature control pipe extending along the treating solution pipe as provided in the conventional apparatus, thereby allowing the treating solution supply system to be compact. An effective heat exchange of the treating solution in the treating solution reservoir is provided to control the temperature of the treating solution efficiently.
Preferably, the temperature control device comprises a temperature control container for receiving the treating solution delivery nozzle, and holding the treating solution reservoir to control temperature of the treating solution in the treating solution reservoir through heat exchange with the treating solution.
With this construction, the temperature control container receives the treating solution delivery nozzle, and holds the treating solution reservoir to control the temperature of the treating solution in the treating solution reservoir through heat exchange with the treating solution. This construction dispenses with the temperature control pipe extending along the treating solution pipe as provided in the conventional apparatus, thereby allowing the treating solution supply system to be compact. An effective heat exchange of the treating solution in the treating solution reservoir is provided to control the temperature of the treating solution efficiently.
Preferably, the temperature control device comprises a nozzle temperature controlling and moving device for holding the treating solution reservoir to control temperature of the treating solution in the treating solution reservoir through heat exchange with the treating solution, and for moving the treating solution delivery nozzle to a predetermined position over the principal surface of the substrate while holding the treating solution reservoir.
With this construction, the nozzle temperature controlling and moving device moves the treating solution delivery nozzle to the predetermined position over the principal surface of the substrate while holding the treating solution reservoir. Thus, this construction dispenses with the temperature control pipe extending along the treating solution pipe as provided in the conventional apparatus, thereby allowing the treating solution supply system to be compact. An effective heat exchange of the treating solution in the treating solution reservoir is provided to control the temperature of the treating solution efficiently. Further, this construction is effective to avoid variations in the temperature of the treating solution in the treating solution reservoir occurring in the course of moving the nozzle to the predetermined position over the principal surface of the substrate.
In another aspect of the invention, a chemical treating apparatus is provided for performing a predetermined treatment of a principal surface of a substrate by delivering a treating solution thereto, the apparatus comprising a treating solution delivery nozzle including a treating solution reservoir adjacent a tip end thereof for storing the treating solution, and a temperature control device for contacting or approaching at least a major part of one of surfaces defining the treating solution reservoir to control temperature of the treating solution in the treating solution reservoir through heat exchange with the treating solution.
According to this invention, the temperature control device contacts or approaches at least a major part of one of the surfaces defining the treating solution reservoir to control the temperature of the treating solution in the treating solution reservoir through heat exchange. The temperature-controlled treating solution in the reservoir is delivered to the substrate for treatment. It is therefore possible to dispense with the temperature control pipe extending along the treating solution pipe as provided in the conventional apparatus, thereby allowing the treating solution supply system to be compact. Moreover, an effective heat exchange of the treating solution in the treating solution reservoir is provided to control the temperature of the treating solution efficiently.
The invention disclosed in this specification relates also to the following chemical treating method and chemical treating apparatus:
(1) A chemical treating method for performing a predetermined treatment of a principal surface of a substrate by delivering a treating solution thereto, the method comprising:
a storage step for storing the treating solution in a treating solution reservoir formed adjacent a tip of a treating solution delivery nozzle for delivering the treating solution to the principal surface of the substrate;
a temperature control step for holding the treating solution reservoir and controlling temperature of the treating solution in the treating solution reservoir through heat exchange with the treating solution; and
a delivery step for delivering the treating solution temperature-controlled in said temperature control step to the principal surface of the substrate.
According to the above chemical treating method (1), the treating solution reservoir is held to control the temperature of the treating solution in the reservoir by heat exchange. The temperature-controlled treating solution in the reservoir is delivered to the substrate for treatment. It is therefore possible to dispense with the temperature control pipe extending along the treating solution pipe as provided in the conventional apparatus, thereby allowing the treating solution supply system to be compact. An effective heat exchange of the treating solution in the treating solution reservoir is provided to control the temperature of the treating solution efficiently.
(2) A chemical treating apparatus for performing a predetermined treatment of a principal surface of a substrate by delivering a treating solution thereto, the apparatus comprising:
a treating solution delivery nozzle for delivering the treating solution to the principal surface of the substrate, the nozzle including a treating solution reservoir adjacent a tip end thereof for storing the treating solution;
a temperature control container for receiving the treating solution delivery nozzle, and holding the treating solution reservoir to control temperature of the treating solution in the treating solution reservoir through heat exchange with the treating solution; and
a standby container disposed below the temperature control container for receiving a discharge opening of the treating solution delivery nozzle lying in the temperature control container, and maintaining the discharge opening on standby in a predetermined atmosphere.
According to the above chemical treating apparatus (2) having the standby container disposed below the temperature control container, the containers may be installed without enlarging a horizontal area occupied by the chemical treating apparatus. The temperature of the treating solution in the treating solution reservoir may be controlled while the discharge opening is maintained on standby in the predetermined atmosphere inside the standby container.
(3) A chemical treating apparatus for performing a predetermined treatment of a principal surface of a substrate by delivering a treating solution thereto, the apparatus comprising:
a treating solution delivery nozzle for delivering the treating solution to the principal surface of the substrate, the nozzle including a treating solution reservoir adjacent a tip end thereof for storing the treating solution;
a standby container for receiving a discharge opening of the treating solution delivery nozzle, and maintaining the discharge opening on standby in a predetermined atmosphere; and
a temperature control container provided separately from the standby container for receiving the treating solution delivery nozzle, and holding the treating solution reservoir to control temperature of the treating solution in the treating solution reservoir through heat exchange with the treating solution.
According to the above chemical treating apparatus (3), the discharge opening of the treating solution delivery nozzle may be maintained on standby in the predetermined atmosphere inside the standby container. The treating solution delivery nozzle to be used next is moved from the standby container into the temperature control container, so that the temperature of the treating solution in the treating solution reservoir may be controlled in the temperature control container. The temperature control container need not correspond in number to the standby container. It is sufficient if at least one temperature control container is provided. This avoids a complication of the apparatus due to a plurality of temperature control containers provided.